Convertible rail-highway shunting locomotive

ABSTRACT

A shunting vehicle for positioning trucks on a railway line wherein the coupling is rotatable, not about a central pin as an axis but by movement guided by angled slots to thereby throw the center of rotation forwardly and avoid displacement of the shunting vehicle wheels from the rails.

United States Patent Yard [54] CONVERTIBLE RAIL-HIGHWAY SHUNTINGLOCOMOTIVE {72] inventor:

[73] Assignee:

William James Yard, Cavan, Australia Aresco Trek-Chief ProprietaryLimited, Cavan, Australia [22] Filed: Nov. 12, 1969 [21] ApplNo; 875,758

[52] US. Cl. ..l05/26 R, l05/26.1, 105/75, 105/90 A, 105/215 C, 213/75[51] Int. Cl. ..B6lc 13/00, B6ld 15/00, B6lf9/00 [58] FieldolSearch..l05/26 R, 73,75,90A,2l5 C, l05/26.l; 213/75 llllllll Illlllll IIIIHIIHFeb. 1, 1972 [56] References Cited UNITED STATES PATENTS 3,380,3974/1968 Yard ..l05/26 R 3,420,191 1/1969 White, Jr ..l05/26 R PrimaryExaminer-Arthur L. La Point Assistant Examiner-Howard BeltranAttorney-Oldham & Oldham [5 7] ABSTRACT A shunting vehicle forpositioning trucks on a railway line wherein the coupling is rotatable,not about a central pin as an axis but by movement guided by angledslots to thereby throw the center of rotation forwardly and avoiddisplacement of the shunting vehicle wheels from the rails.

5 Claims, 4 Drawing Figures PATENTED KB I I972- SHEU13 Pmmmm Imz3538.579

SHEEI 2 OF 3 PATENTEU FEB 11972 31638579 sum 3 M3 CONVERTIBLERAIL-HIGHWAY SHUNTING LOCOMOTIVE This invention relates to a shuntingvehicle of type similar to the shunting vehicle disclosed in theAustralian Pat. No. 261,863.

In the U.S. Pat. No. 3,380,397, a shunting vehicle was disclosed andclaimed wherein a vehicle included a chassis, traction wheels at leastpartly supporting the chassis, the track width of the wheels enablingthem to run on the rails of the railway track, a coupling block at oneend of the vehicle adjacent the traction wheels engageable with acomplementary coupling on a railway vehicle, and lifting wheels operableto apply a lifting force to the coupling block relative to the chassis.This enables part of the weight of the railway vehicle coupled to theshunting vehicle to be transferred to the traction wheels thereof, sothat considerable traction could be obtained even though the wheels ranon the rails.

The usual coupling block, which is described in the U.S. Pat. No. 3,380,397, is provided with a hinge pin, but this is not sufficient toprevent a railway truck from pushing the traction wheels of a shuntingvehicle off the rails, if the truck happens to be negotiating arelatively sharp bend. Accordingly the U.S. Pat. No. 3,380,397 discloseda coupling subchassis rotatable on the main chassis of the vehicle, therotation means being constituted by a simple turntable.

One of the problems however, which is encountered with a simpleturntable for the subchassis carrying the coupling block, is that thetremendous traction force involved will tend to jam the relativelyrotatable parts of the turntable and chassis, and this frictionalengagement can be sufficient to urge the traction wheels of the shuntingvehicle away from the rails so that traction can be lost, and further,so that excessive thrust loads are placed on the bearings of rail guidewheels when these are used.

The main object of this invention is to provide improvements whereby thetendency for lateral displacement of the traction wheels issubstantially reduced, and the invention includes as a featurecomplementary substantially flat members on the chassis of a shuntingvehicle and on a coupling subchassis, pin means extending between thecomplementary members, a bearing plate surrounding each pin means, andcorresponding slots in the other of the members, the slots being angledrelative to the direction of towing force.

By having this arrangement it becomes possible to avoid the use of a pinfor a turntable, and the loading is directly transferred through thebearing plate to the member engaged thereby, and the effective center ofrotation can be transferred thus further forwardly and closer to thecenter of the vehicle than with a rotary table.

An embodiment of the invention is described hereunder in some detailwith reference to and is illustrated in the accompanying drawings inwhich:

FIG. I is a side elevation ofa shunting vehicle,

FIG. 2 is a fragmentary plan (to an enlarged scale) showing the couplingsubchassis,

FIG. 3 is a fragmentary perspective view of same, and

FIG. 4 is a section on plane 4-4-4 of FIG. 3.

According to this embodiment a shunting vehicle is constructedsubstantially similar to the vehicle of the U.S. Pat. No. 3,380,397,being provided with a chassis II, a pair of rubber-tired traction wheels12, a pair of guide wheels I3 carried on retractable arms and adjacentthe rubber-tired traction wheels, a pair of steered wheels 14 which inthis embodiment will be referred to as the front wheels, front guidewheels 15 also carried on retractable arms and adjacent the steeredwheels, a turntable I6 beneath the chassis, a coupling subchassis 17,and a coupling 18 (not shown in FIG. 3). The guide wheels and turntableare respectively arranged to be raised or lowered thereby enabling thevehicle to be moved transversely across a railroad track on its wheels12 and 14, the turntable 16 then being lowered to lift the wheels 12 andI4, the shunting vehicle then being rotated centrally over the railroadtrack, the wheels 12 and 14 beingI supported by the railroad track, andthe guide wheels being owered to engage the railroad track.

The chassis 11 is provided with a flat chassis plate 20 extendingtransversely and this in turn is provided with a pair of spacedupstanding pins 21, these pins supporting upper and lower retentiondiscs 22 in each case and retained by nuts, and a bearing plate 23rotatable on each pin 2!, the bearing plate having side surfaces whichare disposed in slots 24 and engageable against the sides thereof, theslots 24 being in side wings 25 on the coupling subchassis I7. Thecoupling subchassis 17 is provided with a pair of swivel arms 30 whichare arranged to raise and lower the coupling block 18 in pantographfashion, driven by a ram 31 (not shown in FIG. 3). The upper swivel armengages the coupling subchassis by pin means 32 engaging in asubstantially horizontal slot 33 (FIG. 1) to allow relative pitchingbetween the towed vehicle and the shunting vehicle.

Since the slots 24 can throw the effective center of rotation of thecoupling subchassis forwardly as can be seen by studying FIG. 2, theeffective moment tending to displace the traction wheels laterally isgreatly reduced than when a simple turntable is used. This has theeffect of greatly reducing the tendency to displace the vehicle from therails.

Iclaim:

l. A shunting vehicle having a chassis supported on rail-engagingrubber-tired wheels, retractable arms on the chassis, flangedrail-engaging wheels carried by the retractable arms and engaging therails thereby retaining said rubber-tired wheels on the rails, saidchassis having a front end and a rear end, and a coupling subchassis onthe chassis at its rear end, and comprising the improvement of a flathorizontal member on the chassis movably supporting a complementary flathorizontal member on the subchassis, a pair of slots in one of themembers, a corresponding pair of pins in the other member passingthrough the slots, and bearing plates pivot-ally supported by the pinsand slidably engaging the edges defining the slots, the slots beingpositioned symmetrically with respect to the longitudinal centerlinewhich extends between the front and rear ends of said member whichcontains them and diverging away from each other in the direction of thefront of the chassis so that when rotation of the subchassis withrespect to the chassis takes place under operating conditions, saidbearing plates slide within said slots and the effective center ofrotation of the subchassis is transferred forwardly of the slots.

2. A shunting vehicle according to claim I, further comprising acoupling on the coupling subchassis, the coupling being supported by anupper pair of arms and a lower pair of arms, pivot means betweenrespective rear ends of the arms and the coupling, and further pivotmeans between respective front ends of the arms and the subchassis.

3. A shunting vehicle according to claim 2, further comprising a liftingram arranged to lift the coupling relative to the subchassis, thelifting ram extending between the upper pair of arms and the subchassis.

4. A shunting vehicle according to claim I, wherein the pins are weldedto the flat horizontal member on the chassis and extend upwardly throughthe slots, said slots being in the flat horizontal member on thesubchassis, the bearing plates are carried between upper and lowerretention discs on the pins, and nuts on the pins retain the retentiondiscs and bearing plates in respective assemblies.

5. A shunting vehicle according to claim 2 wherein said pivot meansbetween the coupling and the two pairs of arms include a substantiallyhorizontal slot to permit relative pitching between the towed vehicleand the shunting vehicle.

1. A shunting vehicle having a chassis supported on railengagingrubber-tired wheels, retractable arms on the chassis, flangedrail-engaging wheels carried by the retractable arms and engaging therails thereby retaining said rubber-tired wheels on the rails, saidchassis having a front end and a rear end, and a coupling subchassis onthe chassis at its rear end, and comprising the improvement of a flathorizontal member on the chassis movably supporting a complementary flathorizontal member on the subchassis, a pair of slots in one of themembers, a corresponding pair of pins in the other member passingthrough the slots, and bearing plates pivotally supported by the pinsand slidably engaging the edges defining the slots, the slots beingpositioned symmetrically with respect to the longitudinal centerlinewhich extends between the front and rear ends of said member whichcontains them and diverging away from each other in the direction of thefront of the chassis so that when rotation of the subchassis withrespect to the chassis takes place under operating conditions, saidbearing plates slide within said slots and the effective center ofrotation of the subchassis is transferred forwardly of the slots.
 2. Ashunting vehicle according to claim 1, further comprising a coupling onthe coupling subchassis, the coupling being supported by an upper pairof arms and a lower pair of arms, pivot means between respective rearends of the arms and the coupling, and further pivot means betweenrespective front ends of the arms and the subchassis.
 3. A shuntingvehicle according to claim 2, further comprising a lifting ram arrangedto lift the coupling relative to the subchassis, the lifting ramextending between the Upper pair of arms and the subchassis.
 4. Ashunting vehicle according to claim 1, wherein the pins are welded tothe flat horizontal member on the chassis and extend upwardly throughthe slots, said slots being in the flat horizontal member on thesubchassis, the bearing plates are carried between upper and lowerretention discs on the pins, and nuts on the pins retain the retentiondiscs and bearing plates in respective assemblies.
 5. A shunting vehicleaccording to claim 2 wherein said pivot means between the coupling andthe two pairs of arms include a substantially horizontal slot to permitrelative pitching between the towed vehicle and the shunting vehicle.